Wireless power transfer is an increasingly popular capability in portable electronic devices, such as mobile phones, computer tablets, etc. because such devices typically require long battery life and low battery weight. The ability to power an electronic device without the use of wires provides a convenient solution for users of portable electronic devices. Wireless power charging systems, for example, may allow users to charge and/or power electronic devices without physical, electrical connections, thus reducing the number of components required for operation of the electronic devices and simplifying the use of the electronic device.
Wireless power transfer allows manufacturers to develop creative solutions to problems due to having limited power sources in consumer electronic devices. Wireless power transfer may reduce overall cost (for both the user and the manufacturer) because conventional charging hardware such as power adapters and charging chords can be eliminated. There is flexibility in having different sizes and shapes in the components (e.g., magnetic coil, charging plate, etc.) that make up a wireless power transmitter and/or a wireless power receiver in terms of industrial design and support for a wide range of devices, from mobile handheld devices to computer laptops.
When delivering power to an electronic device, whether wirelessly or via a wired connection, electromagnetic interference (EMI) can be an issue. EMI noise may result from the generation of higher harmonics due to non-linear operation in some of the circuitry of the electronic device. In a wireless power transfer configuration, for example, EMI may arise during power conversion in the electronic device (e.g., when the wirelessly received power is being rectified). Typically, an EMI filter may be incorporated on one of the one or more printed circuit boards (PCBs) of the electronic device. However, operation of the EMI filter can result in the generation of heat, which can adversely affect other circuits on the PCB.